Heroin and spice are being smuggled into the John Howard Centre in what is yet another security breach at Homerton’s medium secure unit.

Former patient Lawrence Owen was reportedly left fearing for his life after being threatened with violence by other patients who wanted his money so they could buy drugs.

The East London NHS Foundation Trust (ELFT) which runs the centre in Kenworthy Road, Homerton, told the Gazette it “takes a strong line against drugs and has robust systems to address any suspected drug use or dealing”.

But Lawrence, 25, a convicted arsonist, claims drug taking is rife, and a letter written by managers in March – seen by this newspaper – appears to indicate concerns.

“Richard confirmed taking heroin during his time here, and we are concerned that others were involved and would like to have a conversation about it,” it read.

In January Millfields ward – part of a national pilot for people with ‘dangerous and severe’ personality disorders – was placed on “lockdown” after it was discovered spice and iPhones were being smuggled in.

Since Lawrence was transferred to the ward in December, his mother Alison Miles has noticed a huge deterioration in his physical and mental health.

In January one patient poured a boiling treacle mixture over his head after heating coffee and sugar in the microwave. Lawrence was left with third degree burns, but there was a six-hour delay taking him to Homerton Hospital 500m down the road. It is thought the perpetrator was sent to Broadmoor.

In February he was strangled by another patient while on the phone to his mother, causing Lawrence, who suffers from epilepsy, to suffer a major fit.

He tried to ring his alarm bell but staff had turned it off, and it was left up to Alison to alert them to his plight. He was choking on his vomit by the time staff found him, and rushed to hospital. But the same patient punched him in the face during a group meeting the next day.

“It’s made me really suicidal, despairing, feeling scared, feeling they are not doing anything to protect me,” Lawrence told the Gazette at the time. “It is out of control, and others are feeling the same. It’s a very hostile atmosphere, and no one knows who’s going to blow up and when. I’ve seen patients attacking other patients, and a member of staff getting injured. He was thrown into a wall.”

Lawrence was transferred back to Pentonville on April 24 – but he feels safer there than on Millfields. By then his health was so bad the prison sent him to hospital for severely high blood pressure and uncontrollable fits, and he spent two weeks recuperating before they would admit him.

Alison said: “They shouldn’t really have murderers and rapists and petty crime on the same ward. They all need different treatment. Being in there has made Lawrence so much more ill and vulnerable.

“He was threatened with violence in front of staff for money, so people could buy heroin,” she said. “He was always complaining that people were taking drugs. They would offer to sell him it. He could smell it, and because they live together they all talk about it.

“I used to send him £50 a week, so he could buy things he needed. They ordered in takeaways for them and there’s a little shop in there. But then it came about that he was bullied for the money so they could get their drugs, so I stopped doing it.”

An ELFT spokesman said: “Service users’ physical healthcare is a high priority for us, including caring for complex conditions. Patients are taken for necessary medical appointments.

“The service takes a strong stand against violence towards its service users and staff, and works in conjunction with local police to prosecute where appropriate, and to support anyone who is affected.”

Pc Tom Coe, the new dedicated officer to the centre, told the Gazette: “Drug users and dealers are extremely innovative. I was at court this morning where a user had managed to smuggle drugs into another secure mental health unit. In one sense there’s a lot to be said for the resolve and will of your drug dealer and user, and I sympathise with the John Howard. Mental health is so challenging in so many different ways, and they work hard to keep drugs out.”